1. Technical Field
The present invention relates to an image sensor and an image-capturing apparatus.
2. Related Art
There is a method of capturing an image of an image-capturing target by illuminating it with modulated illumination light and performing lock-in detection of reflected light (please see Patent Document 1, for example).
Patent Document 1: Japanese Patent Application Publication No. 2012-205217
If the area of an image sensor is increased, image-capturing quality is degraded in some cases due to signal delay, attenuation or the like being caused within the sensor.
A first aspect of the present invention provides an image sensor including: a first light-receiving unit that: receives a modulated optical signal having being reflected on an image-capturing target and including a modulated component with an intensity modulated at a predetermined modulation frequency; and outputs a first electrical signal; a second light-receiving unit that: receives a reference optical signal with an intensity modulated in synchronization with the modulated optical signal; and outputs a second electrical signal; and a detecting unit that: is provided to a substrate stacked on a substrate including the first light-receiving unit; refers to the second electrical signal; and detects, from the first electrical signal, a third electrical signal corresponding to the modulated component.
A second aspect of the present invention provides an image-capturing apparatus including the image sensor; and an optical system that forms an image of the image-capturing target on the image sensor.
The summary clause does not necessarily describe all necessary features of the embodiments of the present invention. The present invention may also be a sub-combination of the features described above.